Self-Heating Group Meal Assembly

ABSTRACT

A self-heating, deployable group meal assembly and method of using same that includes a delivery system having individual delivery tubes for conducting the activating liquid from a source of the liquid to each of a plurality of individual heater trays containing heater material. The heater trays are disposed in a stacked configuration, each heater tray including a heater pad comprising a conventional heater material that exhibits an exothermic reaction when contacted with an electrolyte activating liquid, and a food tray containing a quantity of food sufficient for multiple individuals. A source of activating liquid for each heater tray in the assembly ensures uniform and efficient flow of liquid to each such heater tray, the sources of liquid being easily installed in a single step to activate the heater material on demand. In one embodiment of the invention, the heater pads comprise Mg—Fe alloy and the activating liquid comprises saline-water solution.

FIELD OF INVENTION

The present invention relates generally to self-heating meal assemblies, and more particularly to a novel deployable self-heating meal assembly for the preparation of a meal for serving multiple individuals.

BACKGROUND OF INVENTION

Self-heating meal assemblies of the type used, for example, by the military to heat rations of food for an individual are well known. These assemblies have included individual meals referred to as meals ready-to-eat (MREs) used by the military, and group meal assemblies for commercial institutional use.

Background material and descriptions of prior art self-heating meal systems and methods of preparation for both the individual and group type are presented in U.S. Pat. No. 5,355,869 to Pickard et al.

Previously existing ready-to-eat meal assemblies have included individual rations, such as the familiar MRE presently used in the military. However, for military applications in the field and for civilian institutional use, there is a continuing need for reliable and inexpensive self heating multiple meal assemblies where large numbers of persons are to be fed and where separate heat sources, open flames, heated or insulated containers or the like are either not available or otherwise cannot be used for heating the food.

U.S. Pat. No. 5,355,869 describes a self-heating group meal assembly having a plurality of heater trays and institutional sized food pouches and the corresponding plurality of heater assemblies comprising magnesium-iron (Mg—Fe) alloy, a source of activating solution for contacting the heater material, and a metering tube section having a metering orifice aligned with each heater tray for delivering the activating solution to the heater assemblies. Because the activating liquid delivery system comprises a fold-out reservoir and a single piece of continuous tubing connected thereto for delivery of liquid to all four heater trays containing the heater material, the system is cumbersome and hard to use in aligning the four outlet holes in the tubing relative to the trays, and the single piece of tubing has to be cut between each pair of adjacent trays to gain access to the contents of the lower tray.

SUMMARY OF INVENTION

The present invention relates to a self-heating group meal assembly comprising:

-   -   (a) a plurality of food tray assemblies arranged in a stacked         configuration, each food tray assembly including a heater tray         containing an exothermic chemical heater material, and a food         tray supported on said heater tray near said heater material;     -   (b) a plurality of sources of activating liquid for selectively         activating said heater material, each said source including an         outlet having valve means for selectively applying said         activating liquid to said heater material; and     -   (c) conduit means interconnecting each said source with a         corresponding heater tray, each said conduit means having an         inlet attachable to a said source and an outlet disposed near a         corresponding heater tray.

The invention also relates to an improvement in a self-heating group meal assembly having a plurality of food container trays and a corresponding plurality of heater trays containing exothermic chemical heating material supporting the respective food trays, the improvement comprising:

-   -   (a) a plurality of sources of activating liquid for selectively         activating said heater material, each said source including an         outlet having valve means for selectively applying said         activating liquid to said heater material; and     -   (b) conduit means interconnecting each said source with a         corresponding heater tray, each said conduit mean, having an         inlet attachable to a said source and an outlet disposed near a         corresponding heater tray.

The invention further relates to a method for heating a self-heating group meal assembly having a plurality of food trays and a corresponding plurality of heater trays containing exothermic chemical heater material supporting the respective food trays in a stacked configuration, comprising the steps of:

-   -   (a) providing a source of activating liquid for each heater         tray, each said source including an outlet having valve means         for selectively applying said activating liquid to said heater         material in each said heater tray; and     -   (b) providing separate conduit means for interconnecting a         source of activating fluid with a corresponding heater tray,         each said conduit means having an inlet attachable to a said         source and an outlet disposed near a corresponding heater tray.

The present invention solves or substantially reduces problems with prior art self-heating group meal assemblies by providing a self-heating, deployable multiple meal pack assembly and method of using same that includes a novel delivery system having individual delivery tubes for conducting the activating liquid from a source of the liquid to each of a plurality of individual heater trays containing heater material. The heater trays are disposed in a stacked configuration, each heater tray including a heater pad comprising a conventional heater material that exhibits an exothermic reaction when contacted with an electrolyte activating liquid, and a meal tray containing a quantity of food sufficient for multiple individuals. A source of activating liquid for each heater tray in the assembly ensures uniform and efficient flow of liquid to each heater tray, the sources of liquid being easily installed in a single step to activate the heater material on demand. In one embodiment of the invention, the heater pads comprise Mg—Fe alloy, and the activating liquid comprises saline-water solution.

The self-heating group meal assembly may be packed in a shipping container with disposable accessory items, utensils, condiments, beverages and other items for transport to the field.

The invention provides numerous advantages over previously existing systems. The group meal assembly is fully assembled and ready to use, which is a particular advantage for troops in the field. The activating liquid is provided separate from the heater material to preclude accidental premature activation of the heater material, but is supplied in a single step in preparing the meal pack for use and ensures uniform and efficient flow of liquid to each heater tray. The group meal assembly is also lighter in weight and less expensive, and is easier to use and more reliable to operate in the field.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more clearly understood from the following detailed description of representative, embodiments thereof read in conjunction with the accompanying drawings that form a part of this disclosure, wherein:

FIG. 1 is a perspective view of one embodiment of the invention containing four heater trays, and FIG. 1 a is an overall perspective view of a heater tray depicted in FIG. 1;

FIG. 2 is a plan view of a die cut corrugated paperboard member that can be folded to the heater box configuration of FIG. 1;

FIG. 3 is a perspective view in partial cutaway of a subassembly of one heater tray, food tray and heater pad of the FIG. 1 embodiment;

FIG. 4 is a plan view of a die cut corrugated paperboard member that can be folded to the heater tray configuration of FIG. 3;

FIG. 5 is a view in section of a pouch box for containing a plurality of pouches for containing sources of activating liquid useful in the practice of the invention;

FIG. 6 is a perspective view of a pouch box of FIG. 5;

FIG. 7 is a plan view of a die cut corrugated paperboard member that can be folded to the pouch box configuration of FIG. 6;

FIG. 8 is an end view of the connector fittings and supporting structural member shown in the structure of the heater box of FIG. 1;

FIG. 9 is a side view of the connector fittings and supporting structural member shown in the structure of the heater box of FIG. 1;

FIG. 10 is a plan view of the connector fittings and supporting structural member shown in the structure of the heater box of FIG. 1; and

FIG. 11 shows a perspective view in partial cutaway of a meal pack assembly of the invention with a pouch box positioned for installation onto the meal pack assembly.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings, FIG. 1 shows a perspective view of one embodiment of the invention in the form of multiple meal pack assembly 10 including four heater trays 11, and FIG. 1 a is an overall perspective view of a single heater tray 11 included in the FIG. 1 embodiment. FIG. 2 is a plan view of a die cut corrugated paperboard member that can be folded to the heater box configuration of FIG. 1. FIG. 3 shows a perspective view in partial cutaway of a subassembly of a heater tray, food tray and heater pad of the meal pack assembly 10 of FIG. 1. The heater trays 11, heater pads 15 and food trays 13 are contained within a suitably sized corrugated paperboard heater box 12 and sealed within a protective plastic environmental wrap 14 to ensure that the heater pads are protected from the environmental moisture during shipment.

Each heater tray is formed of suitable material for containing the heater pad 15 when activated with activating liquid as described below. In one embodiment of the invention, the heater trays comprise corrugated paperboard having a poly surface for waterproofing. FIG. 4 shows a plan view of a die cut corrugated paperboard member that can be folded to the heater tray 11 configuration of FIG. 3.

The multiple meal pack assembly 10 of the invention as illustrated herein includes four heater tray-food tray assemblies in order to provide heat to four separate foods in amounts sufficient to feed multiple persons. The food is pre-cooked or otherwise ready to eat upon reheating and sealed in the food trays within assembly 10. It should be noted at the outset that a meal pack assembly of the invention can include substantially any number of heater tray-food tray assemblies shown in FIG. 3, as would occur to the skilled artisan practicing the invention, the four illustrated herein being in practice a convenient number not limiting of the invention. Each food tray 13 includes side walls 18 defining an open top 19 heat sealed with a removable protective cover 20 of plastic film or other protective material for hermetically sealing the food 21 within food tray 13.

For simplicity of design and construction of the meal pack assembly and to facilitate production of the assembly, each heater tray 11 is typically produced with a configuration that allows its use in any of the four positions indicated in the representative meal pack assembly 10 shown in FIG. 1. Accordingly, each heater tray 11 includes four inlet openings 22 a, b, c and d (FIG. 3) for receiving liquid conduit means in the form of liquid supply tubes 23 a, b and c, and liquid flow-through connectors 24 a, b, c and d, all of which functions are described more fully hereinbelow. Supply tubes 23 a, b and c may comprise any suitable tubing material and are individually sized in length to connect inlet openings 22 a, b and c to the respective flow-through connectors 24 a, b and c as suggested in FIG. 1. The top heater tray 11 does not require a tube 23 and has a connector (24 d) attached directly thereon through which liquid flow is supplied directly to the top-most heater tray 11.

U.S. Pat. No. 5,335,869, incorporated herein by reference, describes representative specifications for the food and heater trays useful in the practice of the invention. The heater pads 15 typically comprise a selected quantity of Mg—Fe alloy free of any activating material that might cause premature activation of the alloy prior to an intended use. U.S. Pat. No. 4,522,190 to Kuhn et al and U.S. Pat. No. 5,117,809 to Scaringe et al, the entire teachings of which are incorporated by reference herein, provide information on Mg—Fe alloy heaters. The alloy is activated by contact with an electrolyte solution that reacts exothermally to provide heat for the food trays 13. In one embodiment, saline solution is used to activate heaters of Mg—Fe alloy.

Referring now to FIG. 5, shown therein is a view in section of a pouch box 44 for containing a plurality of collapsible, substantially sealed pouches 27 for containing sources of activating liquid (saline solution was used in demonstration of the invention) useful in the practice of the invention for activation of heater pad material 15. FIG. 6 is a perspective view of a pouch box 44 of FIG. 5, and FIG. 7 is a plan view of a die cut corrugated paperboard member used in one embodiment of the invention that can be folded to the pouch box configuration of FIG. 6. Pouches 27 are sized to contain sufficient solution to activate the amounts of alloy contained in heater pads 15 (FIG. 1) as described above. Pouches 27 can be fabricated of any suitable material for the intended purpose of containing the saline activating solution, e.g., a nylon-LDPE (low density polyethylene) sleeve having suitable strength and tear resistance may be used. Each pouch 27 has an outlet defined in one end 29 thereof for receiving a valve 30 configured for mating with a flow-through connector 24 in the controlled delivery of saline solution to a heater tray 11 in using the meal pack assembly 10 as hereinafter more fully described. The lower side 45 of pouch box 44 has openings 28 a, b, c and d defined therein for supporting respective pouches 27 a, b, c and d thereat and spaced in an arrangement so as to align with the connectors 24 a, b, c and d on meal pack assembly 10 (FIG. 1). FIG. 8, FIG. 9 and FIG. 10 show respective end, side, and plan views of the connector fittings and supporting structural member 49 shown in the structure of the heater box of FIG. 1, in an alignment for facilitating insertion of pouch box 44 onto meal pack assembly 10.

In the non-limiting embodiment of the invention illustrated in the figures, representative valve 30 can have the structure suggested in FIG. 5 (such as a Clean-Clic® model supplied by IPN Europe). Each valve 30 has an axially movable valve core 31 biased as at 32 to a normally closed condition, but which is activated to the open position upon inserting a connector 24 into the bottom end 39 of valve 30. Upon moving the core 31 to the open position upon insertion onto a connector 24, outlet 37 is exposed to allow the contents of pouch 27 to flow outwardly of the pouch toward a heater tray 11. A pair of circular flanges 38 a and b formed in end 39 of valve 30 provide means for mounting valve 30 into pouch 27 as suggested in FIG. 2 and for supporting pouch 27 in pouch box 44. Other available valves could be used in the practice of the invention, as could be selected by one skilled in the applicable art, the specific selection not considered limiting of the invention.

FIG. 11 shows a perspective view of a pouch box 44 positioned for installation onto a meal pack assembly 10. Structural member 49 provides structural strength to heater box 12 at connectors 24 and may serve as a guide for installation of pouch box 44. It is noted that heater box 12 has in one end 12 a thereof an access opening 46 for accessing the inlet openings 22 on each heater tray 11 for installation of supply tubes 23 between each heater tray 11 and corresponding connector 24, in the assembly of meal pack assembly 10.

In preparing a meal to eat using the invention in the field, the protective wrap around heater box 12 is first cut or removed so as to allow access to connectors 24 a, b, c and d. Pouch box 44 is then positioned as suggested in FIG. 11 and installed by inserting each connector 24 into a respective valve 30 so as to allow flow of the saline solution from each pouch 27 into the corresponding heater tray 11. Once the saline solution contacts the heater pads 15, the exothermic reaction in each heater tray 11 ensues whereby the food contents of each meal tray 13 are heated. Leaving wrap 14 otherwise intact provides some thermal insulation to meal pack assembly during the heating process.

The invention therefore provides a novel deployable self-heating meal assembly for the preparation of a meal for serving multiple individuals. It is understood that modifications to the invention nay be made as might occur to one with skill in the field of the invention within the scope of the appended claims. All embodiments contemplated hereunder that achieve the benefits of the invention have therefore not been shown in complete detail. Other embodiments may be developed without departing from the spirit of the invention or from the scope of the appended claims. 

1. A self-heating group meal assembly comprising: (a) a plurality of food tray assemblies arranged in a stacked configuration, each food tray assembly including a heater tray containing an exothermic chemical heater material, and a food tray supported on said heater tray near said heater material; (b) a plurality of sources of activating liquid for selectively activating said heater material, each said source including an outlet having valve means for selectively applying said activating liquid to said heater material; and (c) conduit means interconnecting each said source with a corresponding heater tray, each said conduit means having an inlet attachable to a said source and an outlet disposed near a corresponding heater tray.
 2. The self-heating group meal assembly of claim 1 comprising four said food tray assemblies.
 3. The self-heating group meal assembly of claim 1 wherein said heater material comprises magnesium-iron alloy.
 4. The self-heating group meal assembly of claim 1 wherein said food tray is in thermal contact with said heater material.
 5. The self-heating group meal assembly of claim 1 wherein each said food tray contains a re-heatable pre-cooked food item hermetically sealed within said food tray.
 6. The self-heating group meal assembly of claim 1 wherein said sources of activating liquid comprise saline solution.
 7. The self-heating group meal assembly of claim 1 wherein said sources of activating liquid are disposed within a container separate from said stacked configuration.
 8. The self-heating group meal assembly of claim 7 further comprising a flow-through connector for attachment to each respective said valve means in selectively conducting said activating liquid to said heater material.
 9. In a self-heating group meal assembly having a plurality of food trays and a corresponding plurality of heater trays containing exothermic chemical heater material supporting the respective food trays in a stacked configuration, an improvement comprising: (a) a plurality of sources of activating liquid for selectively activating said heater material, each said source including an outlet having valve means for selectively applying said activating liquid to said heater material; and (b) conduit means for interconnecting each said source with a corresponding heater tray, each said conduit means having an inlet attachable to a said source and an outlet disposed near a corresponding heater tray.
 10. The improvement recited in claim 9 comprising four said food trays and four said heater trays.
 11. The improvements recited in claim 9 wherein said heater material comprises magnesium-iron alloy.
 12. The improvement recited in claim 9 wherein said food tray is in thermal contact with said heater material.
 13. The improvement recited in claim 9 wherein each said food tray contains a re-heatable pre-cooked food item hermetically sealed within said food tray.
 14. The improvement recited in claim 9 wherein said sources of activating liquid comprise saline solution.
 15. The improvement recited in claim 9 wherein said sources of activating liquid are disposed within a container separate from said stacked configuration.
 16. The improvement recited in claim 15 further comprising a flow-through connector for attachment to each respective said valve means in selectively conducting said activating liquid to said heater material.
 17. A method for heating a self-heating group meal assembly having a plurality of food trays and a corresponding plurality of heater trays containing exothermic chemical heater material supporting the respective food trays in a stacked configuration, comprising the steps of: (a) providing a source of activating liquid for each heater tray, each said source including an outlet having valve means for selectively applying said activating liquid to said heater material in each said heater tray; and (b) providing separate conduit means for interconnecting a source of activating fluid with a corresponding heater tray, each said conduit means having an inlet attachable to a said source and an outlet disposed near a corresponding heater tray.
 18. The method of claim 17 wherein said heater material comprises magnesium-iron alloy.
 19. The method of claim 17 wherein each said food tray contains a re-heatable pre-cooked food item hermetically sealed within said food tray.
 20. The method of claim 17 wherein said sources of activating liquid comprise saline solution. 